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    <title>Document</title>
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    <script>
        function Foo() {
            Foo.a = function () {
                console.log(1)
            }
            this.a = function () {
                console.log(2)
            }
        }
        Foo.prototype.a = function () {
            console.log(3)
        }
        Foo.a = function () {
            console.log(4)
        }
        Foo.a();
        let obj = new Foo();
        obj.a();
        Foo.a();


        var obj = {
            '2': 3,
            '3': 4,
            'length': 2,
            'splice': Array.prototype.splice,
            'push': Array.prototype.push
        }
        obj.push(1)
        obj.push(2)
        console.log(obj)
    </script>
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